Arrangement for individually extracting flat items from a conveyor system



May 31, 1966 F. BUCHWALD ARRANGEMENT FOR INDIVIDUALLY EXTRACTING FLAT ITEMS FROM A CONVEYOR SYSTEM Filed June 26, 1963 INVENTOR FR/TZ BUCHWALD ATTORNEY United States Patent ARRANGEMENT FOR INDIVIDUALLY EXTRACT- I ING FLAT ITEMS FROM A CONVEYOR SYSTEM Fritz Buchwald, Berlin-Lankwitz, Germany, assignor to International Standard Electric Corporation, New York,

N.Y., a corporation of Delaware Filed June 26, 1963, Ser. No. 290,691 Claims priority, application Germany, July 12, 1962,

' St 19,476 Claims. (Cl. 271-26) a high degree of protection against double extraction,-

they are not foolproof. It is therefore the object of my invention to offer an arrangement for individually extracting stacked flat items of thin material that provides a much higher degree of reliability than heretofore. The known arrangements operate with mechanical-pneumatic extracting devices; that is, with conveyor belts, claws or rollers, by which an item being conveyed is attracted by means of vents connected to a vacuum source and brought into contact with the item being conveyed by means of the belt, the claw or the roller. Another measure for preventing double extraction is to crook or bend the leading item of the items being conveyed, in order to separate it from the pile. Another method is to aim a blast of air at the piled items, with the leading item, however, being separated from the rest of the items only in some spots. My invention refers to such an arrangement.

According to my invention, the extracting device is arranged in a partially or almost totally enclosed housing or extends into such a housing, in which the stacked items are placed and individually extracted through a slot, a stream of compressed air being introduced into said housing to provide air lubrication by the formation of air cushions between the surfaces of the items being conveyed. The housing also has air vents in the immediate vicinity of the extracting device to bring the leading item within range of the extracting device, and, if necessary, also on the housing side opposite the extracting device, in order to hold the subsequent item when extracting the preceding item.

The housing itself may be either completely closed, that is, once the pile to be separated has been inserted, the opening is closed, or the insertion opening may remain without any cover, if it is so dimensioned that the pile of items inserted partially seals off the opening. Since the items being processed are for the most part items of like format, this condition is not difficult to meet.

The above-mentioned and other features and objects of this invention will become more apparent by reference to the following description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a perspective view of my invention in which, for the sake of clarity, the top housing wall has been removed;

FIG. 2 is a side elevational view of the back wall of the housing where separation of the stack takes place;

FIG. 3 is a plan view of the extracting end of the housing with the back wall and the leading items of the stack prior to extracting the first item; and

FIG. 4 is a plan view of the extracting end of the housing according to FIG. 3 immediately after starting to extract the leading item.

Referring now to FIG. 1, there is shown an arrangement in accordance with my invention. Housing 2 is dimensioned so that articles 1 fit snugly between side walls 2b and 2c and also between top wall 2a and bottom wall 2d. For the sake of clarity, upper housing wall 2a is shown removed, but when the arrangement is in use, it is connected to the side walls of the housing. The housings back wall has a cut-out 8, into which pneumatic extracting device 11 fits. The extracting device 11 is an uncomplicated arrangement of five belts and four drums driven by external motive power, which has, cooperating with it, an external source of suction. Piping 12 introduces the suction to a vacuum chamber of a manifold type afiixed to the end of said piping. The vacuum chamber is positioned in said cut-out 8 and has an opening, corresponding to the dimensions of the cut-out, which opening is addressed to the inside of the housing 2. Belt 13, which travels outward from said cut-out at the front, and returns at the rear, being driven by drums 14 and 15, has apertures which admit the suction from the manifoldtype vacuum chamber positioned just below said belt and over the surface of which chamber belt 13 traves outward. Belts 16 and 17 are paired; driven by drums 18 and 15, they travel outward at the front and return at the rear. Both belts 16 and 17 have ridges across their widths on those surfaces which are opposite the surfaces which contact drums 18 and 15. Belts 19 and 20, shown only partially in FIGURE 1, are driven, respectively, by drums 21 and 18 and other given drums of agiven conveying complex. Said given drums and said given conveying complex, are not shown, nor are they within the scope of the subject invention. Arrows drawn in FIGURE 1 signify the direction of rotation of the drums, and the direction of travel in differing planes for each belt, of extracting device 11. As the leading item is separatedout for extraction by means of an air cushion, in a manner explained in the following discussion, it is drawn fast to belt 13, as the suction introduced to the vacuum chamber whichterminates piping 12, and the apertures in belt 13, cooperate to extract said leading item. Belts 16, 17 and 19 receive the extracted leading item and feed it through to the point where belts 19 and 20 pair to convey said leading item to said given conveying complex. In order to allow the extraction of the leading item from the housing 2 by device 11, as described in the foregoing discussion, there is a slot 7 at the point where side wall 20 and back -wall 3 join. To introduce the compressed air, there are air chambers 4, which are attached to the housing at the top and, if necessary, at the bottom and which let compressed air into the housing through openings 5. Air chambers 4 are provided with a compressed air source at 5a. There are additional openings 9, 10, on the back wall and openings 6 on the side walls. The compressed air reaches the atmosphere through these openings. While openings 6 in the side walls serve simply to determine the degree of pressure when the arrangement is working and to loosen the stack in the direction of the extracting end, openings 9 are used to cause the compressed air to press the leading item away from the stack in the vicinity of the extracting device and to bring it into contact with the suction members of extracting device 11. Openings 10 hold the next-following item against the back wall of the housing as soon as extraction of the foremost article begins.

FIG. 2 shows the housings back wall 3 with the cutout into which extracting device 11 fits and openings 9 I in the vicinity of cut-out 8 and openings 10 at the opposite edge of the back wall. FIG. 3 is a plan view of the back wall just before extraction of the leading item. It can be seen that this item, both at the front and back edge, is pressed against the backwall 3 because'of openings 9 and 10, but that in the middle between back Wall 3 and the item and at the edges between the first and the 3 second item air cushions have formed that bring about air lubrication.

FIG. 4 shows the conditions just after the start of extracting the leading item. The latter is already moving with its leading edge through slot 7, but the excess pressure in the housing causes its front and back edges to be pressed against openings 9 and 10, while the air cushions at the back wall and on the next-following item remain intact. As soon as openings 10 are freed through movement of the leading item, the excess pressure in the housing presses the next-following item against those openings. It is thus held fast there, and on the extraction side the air cushion between the leading item and the one behind it keeps the latter 'from reaching slot 7. The third item, controlled by opening 6, keeps a steady distance from item 2 in front of it.

With an arrangement according to my invention, a single extraction from a stack of vouchers can be performed at very high speed, With no fear of double extraction.

While I have described the principles of my invention in connection with specific apparatus, it is to be clearly understood that this description is made only by way of example and not as a limitation to the scope of my invention as set forth in the accompanying claims.

What is claimed is:

1. An arrangement for extracting flat items one at a time: from a stack of such items, said arrangement comprising:

a housing having at least a back wall and a pair of side walls, one of said side walls having an opening formed near the junction of said side wall with said back wall for the exit of items extracted from the said stack of items arranged within said housing with the'planes of the items of said stack substantially parallel to the plane of said back Wall, and said back wall having an opening formed therein near said junction of said side wall with said back wall;

an extracting device for propelling away from said housing aleading item separated from said stack within said housing, said extracting device including at least one porous endless belt mounted on rotating drums and arranged for motion with one surface of said porous endless belt oriented in said opening in said back wall and substantially in the plane of said back wall; and

means for directing an airstream into said housing in a direction substantially parallel to the plane of said back wall whereby said airstream tends to separate said leading item from the remaining items of said stack by pressing a leading edge of said leading item 4, against a surface of said porous endless belt while simultaneously restraining the remaining items of said stack against motion away from said stack.

2. An arrangement in accordance with claim 1 further including additional endless belts arranged on rotating drums with at least one surface of each said additional endless belt having a portion thereof oriented in a plane substantially aligned with the plane of said one surface of said first-mentioned endless belt for receiving from said first-mentioned endless belt a leading item extracted from said stack by said first-mentioned endless belt.

3. An arrangement in accordance with claim 2 in which at least one said additional endless belt has a ridged surface for enhancing the traction between said surface of said endless belt and said leading item extracted from said stack.

4. An arrangement in accordance with claim '1 wherein said means for directing an airstream comprises a manifold coupled to a source of compressed air and having openings through which said airstream is directed from said manifold in a direction substantially parallel to the plane of said back Wall.

5. An arrangement in accordance with claim 1 in which said back wall is provided with openings near the respective ends thereof through which a portion of said airstream is permitted to leave saidhousing, whereby a pressure differential is established between the two surfaces of the respective ends of said leading item, thereby tending to press the leading end of said leading item against said first-mentioned endless belt and the trailing end of said leading item against said back wall.

References Cited by the Examiner UNITED STATES PATENTS 1,460,314 6/1923 Deck 271-26 2,806,696 9/1957 Bishop 271--32 2,819,075 1/1958 Noon 27126 2,952,457 9/1960 Fliegner 271-26 X 2,970,834 2/1961 Martin et-al. 27126 3,079,147 2/1963 Childs 27126 3,099,442 7/1963 Wendricks et a1. 271--32 3,105,681 10/1963 Bishop et al. 27132 3,136,539 6/1964 Lyman 271-26 FOREIGN PATENTS 985,269 3/1951 France.

ROBERT B. REEVES, Primary Examiner.

RAPHAEL M. LUPO, Examiner. I C. AOUSSAT, W. MCCARTHY, Assistant Examiners. 

1. AN ARRANGEMEENT FOR EXTRACTING FLAT ITEMS ONE AT A TIME FROM A STACK OF SUCH ITEMS, SAID ARRANGEMENT COMPRISING: A HOUSING HAVING AT LEAST A BACK WALL AND A PAIR OF SIDE WALLS, ONE OF SAID SIDE WALLS HAVING AN OPENING FORMED NEAR THE JUNCTION OF SAID SIDE WALL WITH SAID BACK WALL FOR THE EXIT OF ITEMS EXTRACTED FROM THE SAID STACK OF ITEMS ARRANGED WITHING SAID HOUSING WITH THE PLANES OF THE ITEMS OF SAID STACK SUBSTANTIALLY PARALLEL TO THE PLANE OF SAID BACK WALL, AND SAID BACK WALL HAVING AN OPENING FORMED THEREIN NEAR SAID JUNCTION OF SAID SIDE WALL WITH SAID BACK WALL; WALL; AN EXTRACTING DEVICE FOR PROPELLING AWAY FROM SAID HOUSING A LEADING ITEM SEPARATED FROM SAID STACK WITHIN SAID HOUSING, SAID EXTRACTING DEVICE INCLUDING AT LEAST ONE POROUS ENDLESS BELT MOUNTED ON ROTATING DRUMS AND ARRANGED FOR MOTION WITH ONE SURFACE OF SAID POROUS ENDLESS BELT ORIENTED IN SAID OPENING AN SAID BACK WALL AND SUBSTANTIALLY IN THE PLANE OF SAID BACK WALL; AND MEANS FOR DIRECTING AN AIRSTREAM INTO SAID HOUSING IN A DIRECTION SUBSTANTIALLY PARALLEL TO THE PLANE OF SAID BACK WALL WHEREBY SAID AIRSTREAM TENDS TO SEPARATE SAID LEADING ITEM FROM THE REMAINING ITEMS OF SAID STACK BY PRESSING A LEADING EDGE OF SAID LEADING ITEM AGAINST A SURFACE OF SAID POROUS ENDLESS BELT WHILE SIMULTANEOUSLY RESTRAINING THE REMAINING ITEMS OF SAID STACK AGAINST MOTION AWAY FROM SAID STACK. 